Okura Nobuhiko

写真a

Title

Instructor

Researcher Number(JSPS Kakenhi)

90152090

Current Affiliation Organization 【 display / non-display

  • Duty   University of the Ryukyus   Graduate School of Medicine   Instructor  

Academic degree 【 display / non-display

  • Kyushu University -  Doctor of Agriculture

External Career 【 display / non-display

  • 1998.02
     
     

    - , University of the Ryukyus, Faculty of Medicine, Medicine, Research Assistants  

  • 1998.02
     
     

     

  • 2010.04
     
     

    - , University of the Ryukyus, Graduate School of Medicine, Research Associate  

  • 2010.04
     
     

     

  • 2010.04
     
     

    University of the Ryukyus, Graduate School of Medicine, Research Associate  

Research Interests 【 display / non-display

  • Reproductive biology,Andorology,Anatomy

  • 生殖生物学

  • アンドロロジー

  • Reproductive biology

  • Andorology

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Research Areas 【 display / non-display

  • Life Science / Animal physiological chemistry, physiology and behavioral biology

  • Life Science / Anatomy

  • Life Science / Animal physiological chemistry, physiology and behavioral biology

Research Theme 【 display / non-display

  • Functional Significance of Atypical Spermatozoa

  • Cytological Studies on Dimorphic Spermatogenesis

Published Papers 【 display / non-display

  • Disassembly of the apical junctional complex during the transmigration of Leptospira interrogans across polarized renal proximal tubule epithelial cells.

    Sebastián I, Okura N, Humbel BM, Xu J, Hermawan I, Matsuura C, Hall M, Takayama C, Yamashiro T, Nakamura S, Toma C

    Cellular microbiology ( Cellular Microbiology )  23 ( 9 ) e13343   2021.09 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

  • Development and persistence of neuropathic pain through microglial activation and KCC2 decreasing after mouse tibial nerve injury.

    Kosaka Y, Yafuso T, Shimizu-Okabe C, Kim J, Kobayashi S, Okura N, Ando H, Okabe A, Takayama C

    Brain research ( Brain Research )  1733   146718   2020.04 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

  • Characterizing interactions of Leptospira interrogans with proximal renal tubule epithelial cells.

    Yamaguchi T, Higa N, Okura N, Matsumoto A, Hermawan I, Yamashiro T, Suzuki T, Toma C

    BMC microbiology ( BMC Microbiology )  18 ( 1 ) 64   2018.07

    Type of publication: Research paper (scientific journal)

  • Effects of fluid secreted from the uterus on duration of fertile egg production in hens, and survivability and penetrability of fowl sperm in vitro.

    Muslah U. Ahammad, Tomoko Miyazato, Chiaki Nishino, Hideki Tatemoto, Nobuhiko Okura, Shin Okamoto, Yasuhiro Kawamoto, Tadashi Nakada

    The Journal of Poultry Science   50 ( 1 ) 74 - 82   2013 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

     View Summary

    In this study, whether the secretion of the uterine fluid (UF) exerts a role in the prolongation of functional life-span of the sperm in the hen oviduct was evaluated. The sperm were subjected to upper vaginal artificial insemination (AI) in the vicinity of the utero-vaginal junction (UVJ) under conditions of either non-secretion, plumping fluid (PF) secretion, or calcifying fluid (CF) secretion of the uterus of hens. Aliquots of the sperm were also subjected to in vitro storage at 41°C for 0, 2, 4, and 6 h in Lake’s solution (LS), PF and CF. Following AI, the exposure of the sperm to either PF or CF secretion resulted in a remarkably a longer duration of the fertile egg production compared to when the AI was performed during the non-secretory phase of the uterus (P<0.05). Similarly, the in vitro exposure of the sperm to PF and CF during storage resulted in increased survivability and penetrability of the sperm compared with storage in LS (P<0.05). In particular, distinct functional differences (P<0.05) were observed between the sperm stored in vivo and in vitro under PF and CF conditions. The sperm inseminated in the presence of PF secretion exhibited a longer period of fertile egg production, and the sperm stored in PF in vitro exhibited a higher capacity for survival and penetration into the inner perivitelline layer (IPL) than those inseminated in the presence of CF secretion or were stored in vitro in CF, respectively, indicating that exposure of the sperm to the UF might influence sperm function. In conclusion, the in vivo and in vitro findings suggest that the secretion of UF in the oviduct of hens may prolong sperm survival and maintain the fertility potential of the fowl sperm.

  • Characteristic features of intracellular pathogenic Leptospira in infected murine macrophages.

    Toma C, Okura N, Takayama C, Suzuki T.

    Cell Microbiol. ( Blackwell Publishing Ltd. )  13 ( 11 ) 1783 - 1792   2011.11 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

     View Summary

    Leptospira interrogans is a spirochaete responsible for a zoonotic disease known as leptospirosis. Leptospires are able to penetrate the abraded skin and mucous membranes and rapidly disseminate to target organs such as the liver, lungs and kidneys. How this pathogen escape from innate immune cells and spread to target organs remains poorly understood. In this paper, the intracellular trafficking undertaken by non-pathogenic Leptospira biflexa and pathogenic L. interrogans in mouse bone marrow-derived macrophages was compared. The delayed in the clearance of L. interrogans was observed. Furthermore, the acquisition of lysosomal markers by L. interrogans-containing phagosomes lagged behind that of L. biflexa-containing phagosomes, and although bone marrow-derived macrophages could degrade L. biflexa as well as L. interrogans, a population of L. interrogans was able to survive and replicate. Intact leptospires were found within vacuoles at 24 h post infection, suggesting that bacterial replication occurs within a membrane-bound compartment. In contrast, L. biflexa were completely degraded at 24 h post infection. Furthermore, L. interrogans but not L. biflexa, were released to the extracellular milieu. These results suggest that pathogenic leptospires are able to survive, replicate and exit from mouse macrophages, enabling their eventual spread to target organs.

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Other External funds 【 display / non-display

  • Project Year: 1900.01  -  1900.01 

    Direct: 0 (YEN)  Overheads: 0 (YEN)  Total: 0 (YEN)

  • Project Year: 1900.01  -  1900.01 

    Direct: 0 (YEN)  Overheads: 0 (YEN)  Total: 0 (YEN)